Process of removing paint and varnish.



PATENIED NOV. 26, 1907.

J. M. WILSON. PROCESS OF REMOVING PAINT AND VARNISH.

APPLICATION FILED AUG. 1, 1907.

UNITED STATES PATENT OFFICE.

JOHN MJWILSON, OF MONTCLAIR, NEW JERSEY.

. To all whom it may concern:

PROCESS OF REMOVING PAINT AND VARNISH.

Be it known that I, JOHN M. WILsoN, a citizen of the United States, residin at Montclair,in tlie county of Essex'an State of New Jersey, have invented certain new and useful Improvements in Processes of Removing Paint and Varnish, of which the following is a specification.

My invention relates to improvements in those processes of removing dried films of aint and varnish, wherein non-alkaline, lmforming compositions containing volatile paint and varnish solvents, or non-alkaline compositions consisting entirely of volatile aint and varnish solvents or other whol y volatile compounds, are employed to dissolve the said films and cut the oily ingredients thereof, thereby rendering them susceptible of being-readily removed with a cloth, scraper or the like.

Heretofore, when using film forming, nonalkaline removers, commonly termed neutral removers'because of the absence of corrosive alkalies therein, it hasbeen the uni versal practice to 2, ply the same to the surfaces to be treated by manual dipping of an ordinary paint brush into a body of the retacle, as the characterlsticproperty sessed by said removers is that of Immediate mover contained in an open-mouthed recepposformation of a viscous, impervious film upon exposure to the atmosphere, and tlus property apparently precluded their application in any other manner.

Moreover, the attempted application by atomization of a volatile remover, i. 6., a remover free from aqueous, acid and alkaline solvents, etc. or,

in other .words, the simultaneous ejection of a jet of air and liquid thoroughly commin- 40 gled through a common outlet nozzle, as is one of the customary methods employed in the ap lieation of paint to large, exposed areas .0? the particular surfaces to be treated, results in the rapid diminution in strength of' the said neutral remover owing to the rapid volatilizationof the volatile solvents contained therein, which solvents are ,me-

chanically. entrained and mechanically volatilized by the commingled air. Moreover,

the presence of numerous air bubbles throughout the liquid not only prevents perfect contact of the remover with the dried film of paint orevarnish to be treated, but also the said air bubbles tend to clog up the minute pores of the said films and prevent the penetration of the volatile solvents into Specification of Letters Patent.

Application filed August 1. 1907- Serial No. 386.651.

l 'atented Nov. 26, 1907.

1tillie pores and beneath the paintor varnish The objects of my invention are to secure an efliclent penetration of a film forming neutral remover, or a non-film-forming neutral remover m its normal conditlon into the pores of the palnt or varnish surfaces treated and to more efiectively retard the evaporat1on of the volatile solvents of said removers,

' and particularly of the non-film-fprining removers, by forcibly projecting the same into and through, the said paint or varnish film treated. In addition to these features, I am also enabled to conserve the strength of the remover and maintain the same in a uniform condition throughout the period of treatment and the escape of objectionable vapors ofan explosive nature or of a poisonousor deleterious nature is thereby substantially of a modified nozzle having a brush-like envelop therefor.

Referringto the drawings the reference numeral 1 re resents a pressure-tank havingan intake-va ve a, the numeral 2 the handle of an air-pump adapted to create pressure in said tank, and the numeral 3 a flexible hose or connection adapted to be attached to the curved hollow extension-arm'5 communicatin with the nozzle 4. A lever 6, havin an 0 -set 13, is ada ted to operate the va vestem in said nozz e, as hereinafter described;

The numeral 7 designates the barrel ofthe air-pump serving to create pressure within "the said pressure-tank. A p1ston-rod8, pro,-

vided at its upper end with a lug 8. which is adapted to enter and be-retained within a bayonet-slot 1, on the upper end ofsaid tank, connects a plunger-piston 9 provided with an upwardly-seating valve 1), with a handle 2,

and thusin the manner well understood compressed air may be collected above the body of liquid which may be introduced within the pressure-tank by the reciprocal operation of the handle 2, whereby air escapes through which is secured to the end of said valve-stem 12, and the said spring thus normally causes the cylindrical piston 16 to close the opening 1n the end of the hollow curved extension-'- arm '5, and thus normally the flow of liquid through the said needle-valve in the thimble 18 1s prevented. A nut 19 serves to lock the thimble 18, which is threaded into the end of said nozzle 4 and permits of the accurate ad ustment of the thimble and the regulat1on of the size of the outlet therein. The lever-arm 6 is pivoted at 20,, as shown, in such a. manner that normally the off-set end 13 extends transversely across the rear end of the nozzle 4, which serves as a support for sald off-set end when in this position.

In Fig. 2 is CllSOlOSGdlfi. modified form of nozzle adapted for applying heavy or thick removers 111 a manner analo ous to that herein descrlbed for the app ication of thin, readily flowing neutral removers, either contalnlng film-forming ingredieiits or not. The numeral 21 designates a hollow pipe which is adapted to be threaded into the head 22 of a hollow brush. The projecting end of said pipe 1s provided with a thread adapted to fit the corresponding thread in the end of the nozzle 4. The said pipe 21 extends some- -what beyond the perforated head' of said brush and is provided with oppositelydis posed lateral openings communicating with the hollow interior of said pipe, as shown at 23. The bristles 24 are arranged on the brush 1n the usual manner with the exception that they are moved in order to permit 1 of the insertion of the hollow pipe 21 at the center of said head 22 and centrally disposed withlnsaid ,bristles. i I Havingthus described the construction of the apparatus usedin carrying out mvprocess, I w ll now proceed to describe the said process 1n detail.

A neutral remover consistin for example, of one quart of methyl 9.100 01,- to which is added a solution of two and a half ounces of paraffin wax and three quarts of benzol (benzene), and also a viscous solution (if collodlon, preferably about two and a-- half ounces, said collodion consisting of ninety: two and a half per cent. of an ethyl acetate and alcohol mixture, and seven anda'half per cent. of nine-cellulose, preferablypyroxylin, is placed in said container or presthree quarts of benzol (benzene).

sure-tank, preferably sufficient to occupy three-quarters of the capacity thereof. Compressed air is then ejected into said tank by reciprocating the iston 9 about ten or twelve times, and t en locking thesaid piston rod 8 in order to prevent movement thereof due to the pressure of confined air.

Various removers may be employed for this purpose, but preferably when applying the remover in the form of a spray and without the em loyment of a brush as heretofore described, employ a mixture vconsisting of one quart of methyl alcohol and three quarts of benzol (benzene), said mixture being entirely free from any film-forming ingredients.

the brush-like nozzle When employing V heretofore. described, the following mixture can be advantageously employed: (1) one quart of methyl alcohol, to whichis added a solution of one-half pound of beeswax in To this is added a viscous solution to the amount of approximately one pound, said viscous mixture consisting, substantially of ninety-two and a half per cent. of a mixture of alcohol and ethyl acetate, the latter in relatively small quantities, and seven and a half per cent. of nitro-cellulose, preferably pyroxylin, although other nitro-celluloses of a lower degree of nitration may be substituted therefor. Dr again the following non-aqueous.

remover may be employed: (2) A mlxture of one quarter pound of bees Wax, one quar ter pound of paraffin, or if desired one-eighth pound of paraffin and one-eighth pound of stearin may be employed in lieu of the paraflin, is heated with one half to threequarters of a pound of carbolic acid crystals (phenol) until substantially dissolved therein and to this mixture is added seven pounds of a second mixture consisting of six pounds of methyl alcohol and one pound of a .collodion mixture containing approximately 92 1/2% of solvent, for example ethyl alcohol and ethyl acetate, the latter in relatively small quantities, and 7 1/2% of nitro-cellulose, or

other compounds of a similar nature, as ace- 1 tate of cellulose.

Having created a pressure within the tank varnish in sufiicientquantities to materially retard the evaporation of the volatile non-' aqueous solvents, the remover can be easily applied to the surface to be treated by exerting a slightv pressure uponthe lever 6,

whereupon a substantiallycontinuous jet of the remover free from commingled air-bubbles, is ejected throughmthe opening in the thimble 18, adjusted to the deslre degree as heretofore stated. The flexible hose 3 is manipulated as desired in order that the nozzle 4 may be brought in proximitynfo the surface to be treate i The application of the liquid 7 remover,

whether as herein claimed, the remover utilized is free from waxy, film-forming bodies and of such a nature that when applied with a brush inthe ordinary manner its efficiency is destroyed by the rapid evaporation whereby its use is rendered impracticable, is so instantaneous, subsequent to its removal from the container or pressure tank, that the loss by eva oration is practically m'l. Moreover since tlib remover 1s forcibly injected into the pores of the film of paint or varnish treated and beneath said film, even though no waxy, film-forming ingredients are present, the escape of the non-aqueous volatile solvents of paint and varnish is materially retarded.

The remover free from, aqueous acid and alkaline solutions of paint and varnish solvents in sufficient amounts to of themselves materially retard the evaporation of the volatile, non-aqueous solvents of paint and varnish, while preferably used in this apparatus, owing to'the fact that it is an auto-wash,

'i. e., no auxiliary wash of benzin or alcohol is required to sup lement the treatment and prior to the app ication of fresh coats of paint or varnish, is by no means the only type of remover which can be used, as hereto ore explained. Preferably when applying comparatively viscous, waxy removers, the fountam-brush shown 1n F1g. 2 1s employed, the jet of remover being injected into the hollow stem of pipe 21 and thence into the V-shaped space 25 immediately below the enlargement 26 surrounding the pipe 21.

Valves of the usual t e common to 'air-' pumps, namely, a, b, an 0 are provided as shown and if desired an additional nut 19 may be inserted as shown to permit of more accurate adjustment of the needle-valve 17.

v Removers which are capable of acting as auto-washes, such as those containing only volatile solvents and free from acids, alkalies and film-forming ingredients in sufficient amounts to materially retard the evaporationof the volatile, non-aqueous solvents of paint and varnish are especially valuable in practice, owing to the fact that while benzene, benzin, gasolene and the like raise removers, consisting for example of one part methyl alcohol and three parts benzene, oes

- .'not require sand-papering asthe' grain of-the wood is entirely unaffected thereby.

such as ammoniac grain of the wood, necessitating subse-,

The-term dried as used in the specification and claims in connection with paint and varnish surfaces, relates to surfaces which have been oxidized orwea'thered.

The term non-aqueous solvent :or'solvents, used in the specification and claims relates to paint and varnish solvents which are commonly termed non-a ueous, as distinguished from a ueous aci solvents, such as acetic acid, an' a ueous alkaline solvents,

:31 solutions, and the like, which, as commercially, known contain large amounts of water, for example commercial acetic acid' contains from to 40% of water, and usually the former amount.

Having thus described my invention, I claim:

l. The process of removing paint and varnish, which consists in causing a pneumatic+ ally-propelled jet of a paint and varnish remover, containing highly volatile non-aqueous solvent of dried films of paint and varnish and free from suflicient amounts of aqueous acid and alkaline solutions capable nish, Whic consists in causing a pneumatically-propelled jet of a aint and varnish remover, containing highl ous solvent of dried films of paint and varnish and free from su'llicient amounts of waxy, film-forming compounds to produce a film and efiectivel retard the evaporation of the highly volatile solvent, upon exposure to the atmosphere, to impinge against an exposed surface of dried paint or varnish,

whereby the evaporation of the volatile ingredients is substantially retarded and an efficient penetration of the said solvent into the pores of and beneath the filmof paint or varnish treated is secured, and then removing the softened, slush-like film resulting from said treatment, substantially as described.

y volatile, non-aque- In testimony whereof, I have signed my I name to this specification in the presence of two subscribing witnesses, this twenty-third day of July 1907.

JOHN M. WILSON.

Witnesses:

V W. H. SWENARTON,

CHARLES E. WIRz. 

